Since 2015, California law says you can't disqualify a potential donor because of cannabis use. Still, it is a factor that doctors take into account when determining who is the best candidate.

Within 10 days of being sent to the hospital for pneumonia, 19-year-old Riley Hancey's lungs collapsed. He needed a new pair, but the University of Utah hospital refused to put him on the transplant list. Hancey's dad says he had tested positive for THC.

"Riley was not a big pot smoker," said Hancey's dad Mike. "He did smoke pot. He's a 19-year-old ski guy. It's not like he's a smoker for 30 years and has deteriorating lungs because of that."

The hospital said in a statement, "We do not transplant organs in patients with active alcohol, tobacco, or illicit drug use or dependencies until these issues are addressed."